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Inhibition of microorganisms by topical anesthetics

J Kleinfeld1, P P Ellis

  • 1Division of Ophthalmology, University of Colorado Medical Center, Denver, Colorado 80220.

Applied Microbiology
|November 1, 1967
PubMed

Insights

This study investigated topical anesthetics and preservatives against microbial growth. Tetracaine, benoxinate, cocaine, chlorobutanol, and butyl p-hydroxybenzoate showed varying inhibition against Pseudomonas aeruginosa, Staphylococcus albus, and Candida albicans.

Area of Science:

  • Microbiology
  • Ophthalmology
  • Pharmacology

Background:

  • Topical anesthetics are used in ophthalmic procedures.
  • Preservatives are added to ophthalmic solutions.
  • Potential for microbial contamination exists.

Purpose of the Study:

  • To evaluate the antimicrobial effects of common topical anesthetics and their preservatives.
  • To determine the susceptibility of key microorganisms to these agents.

Main Methods:

  • In vitro testing of four topical anesthetics (proparacaine HCl, tetracaine HCl, cocaine HCl, benoxinate HCl) and two preservatives (chlorobutanol, butyl p-hydroxybenzoate).
  • Assessing the growth inhibition of Pseudomonas aeruginosa, Staphylococcus albus, and Candida albicans.

Main Results:

  • Proparacaine HCl inhibited Candida albicans but not Pseudomonas aeruginosa or Staphylococcus albus.
  • Tetracaine HCl, benoxinate HCl, cocaine HCl, chlorobutanol, and butyl p-hydroxybenzoate demonstrated varying degrees of inhibition against all three tested organisms.

Conclusions:

  • Different topical anesthetics and preservatives possess distinct antimicrobial properties.
  • The choice of anesthetic and preservative may influence the risk of microbial growth in ophthalmic preparations.

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